The Marshall characteristics of stone mastic asphalt mixtures made by pyrolysis polypropylene

Recently, industrialization, population and consumption have been increasing in the world as a result problems in finding new resources have increased. The rapid consumption of natural resources causes future concerns and therefore it has become important to utilize the waste materials generated. Utilizing waste materials will provide significant benefits both environmentally and economically. The scope of this thesis, taking into account these effects, waste polypropylene was pyrolyzed and Marshall Properties were investigated. In this study, waste polypropylene (PP) was pyrolyzed and the proportions of pyrolysis products (solid, liquid and gas) were calculated. Modified bitumen was prepared by mixing pyrolysis solid product with pure 50/70 bitumen in 5% rate. In order to examine the effect of additives on pure bitumen; Penetration and softening tests were carried out and compared with pure 50/70 bitumen and modified bitumen with 4.5% SBS. It was observed that the penetrations of the modified bitumen decreased and the softening points increased compared to the pure bitumen. Three different types of mixtures in the study; Mixtures of bitumen modified with 5% PPP, bitumen modified with 4.5% SBS and unmodified (pure 50/70 bitumen) were prepared. 18 briquettes were prepared from each of the modified and unmodified mixtures obtained and subjected to Marshall Test. At the end of the experiment, optimum bitumen ratios were found as 6.3%, 6.6% and 6.2%, respectively. Considering the Marshall Test properties according to the optimum bitumen, the stability values are almost the same, but there is a difference in the air gap and flow values.